Perovskite LaFeO(3)/montmorillonite nanocomposites: synthesis, interface characteristics and enhanced photocatalytic activity

Perovskite LaFeO(3)/montmorillonite nanocomposites (LaFeO(3)/MMT) have been successfully prepared via assembling LaFeO(3) nanoparticles on the surface of montmorillonite with citric acid assisted sol-gel method. The results indicated that the uniform LaFeO(3) nanoparticles were densely deposited onto the surface of montmorillonite, mainly ranging in diameter from 10 nm to 15 nm. The photocatalytic activity of LaFeO(3)/MMT was evaluated by the degradation of Rhodamine B (RhB) under visible light irradiation, indicating that LaFeO(3)/MMT exhibited remarkable adsorption efficiency and excellent photocatalytic activity with the overall removal rate of RhB up to 99.34% after visible light irradiation lasting for 90 min. The interface characteristic and possible degradation mechanism were explored. The interface characterization of LaFeO(3)/MMT suggested that LaFeO(3) nanoparticles could be immobilized on the surface of montmorillonite with the Si-O-Fe bonds. The abundant hydroxyl groups of montmorillonite, semiconductor photocatalysis of LaFeO(3) and Fenton-like reaction could enhance the photocatalytic degradation through a synergistic effect. Therefore, the LaFeO(3)/MMT is a very promising photocatalyst in future industrial application to treat effectively wastewater of dyes.